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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 13 |
| 6 | 26 |
| 7 | 62 |
| 8 | 132 |
| 9 | 274 |
| 10 | 614 |
| 11 | 1315 |
| 12 | 2955 |
| 13 | 6423 |
| 14 | 14058 |
| 15 | 30838 |
| 16 | 67170 |
| 17 | 147553 |
| 18 | 322304 |
| 19 | 706400 |
| 20 | 1546128 |
| 21 | 3382752 |
| 22 | 7408261 |
| 23 | 16208271 |
| 24 | 35489093 |
| 25 | 77672999 |
| 26 | 170021833 |
| 27 | 372181083 |
| 28 | 814611385 |
| 29 | 1783211187 |
| 30 | 3903138418 |
| 31 | 8543748906 |
[1,1,2,4,13,26,62,132,274,614,1315,2955,6423, 14058,30838,67170,147553,322304,706400,1546128, 3382752,7408261,16208271,35489093,77672999, 170021833,372181083,814611385,1783211187, 3903138418,8543748906] |